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            <small>
              <a href="#Procedure">Procedure<br></a>
              <a href="#Abstract">Abstract<br></a>
              <a href="#Required_Reading">Required_Reading<br></a>
              <a href="#Keywords">Keywords<br></a>
              <a href="#Brief_I/O">Brief_I/O<br></a>
              <a href="#Detailed_Input">Detailed_Input<br></a>

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              <td style="vertical-align: top; width: 50%; text-align: center;">
              <small>               <a href="#Detailed_Output">Detailed_Output<br></a>
              <a href="#Parameters">Parameters<br></a>
              <a href="#Exceptions">Exceptions<br></a>
              <a href="#Files">Files<br></a>
              <a href="#Particulars">Particulars<br></a>
              <a href="#Examples">Examples<br></a>

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              <small>               <a href="#Restrictions">Restrictions<br></a>
              <a href="#Literature_References">Literature_References<br></a>
              <a href="#Author_and_Institution">Author_and_Institution<br></a>
              <a href="#Version">Version<br></a>
              <a href="#Index_Entries">Index_Entries<br></a>
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<h4><a name="Procedure">Procedure</a></h4>
<PRE>
   void gfuds_c (  void             ( * udfunc ) ( SpiceDouble       et,
                                                   SpiceDouble     * value ),

                   void             ( * udqdec ) ( void ( * udfunc ) 
                                                        ( SpiceDouble   et,
                                                          SpiceDouble * value ),

                                                   SpiceDouble       et,
                                                   SpiceBoolean    * isdecr ),

                   ConstSpiceChar     * relate,
                   SpiceDouble          refval,
                   SpiceDouble          adjust,
                   SpiceDouble          step,
                   SpiceInt             nintvls,
                   SpiceCell          * cnfine,
                   SpiceCell          * result )

</PRE>
<h4><a name="Abstract">Abstract</a></h4>
<PRE>
 
   Perform a GF search on a user defined scalar quantity.
 </PRE>
<h4><a name="Required_Reading">Required_Reading</a></h4>
<PRE>
   <a href="../req/gf.html">GF</a>
   <a href="../req/windows.html">WINDOWS</a>
 </PRE>
<h4><a name="Keywords">Keywords</a></h4>
<PRE>
   EVENT
   GEOMETRY
   SEARCH
   WINDOW


</PRE>
<h4><a name="Brief_I/O">Brief_I/O</a></h4>
<PRE>
 
   VARIABLE  I/O  DESCRIPTION
   --------  ---  --------------------------------------------------

   udfunc     I   Name of the routine that computes the scalar value
                  of interest at some time.
   udqdec     I   Name of the routine that computes whether the 
                  current state is decreasing.
   relate     I   Operator that either looks for an extreme value
                  (max, min, local, absolute) or compares the
                  geometric quantity value and a number.
   refval     I   Value used as reference for geometric quantity 
                  condition.
   adjust     I   Allowed variation for absolute extremal 
                  geometric conditions.
   step       I   Step size used for locating extrema and roots.
   nintvls    I   Workspace window interval count
   cnfine    I-O  SPICE window to which the search is restricted.
   result     O   SPICE window containing results.
 </PRE>
<h4><a name="Detailed_Input">Detailed_Input</a></h4>
<PRE>
   udfunc     the name of the external routine that returns the 
              value of the scalar quantity of interest at time ET.
              The calling sequence for &quot;udfunc&quot; is:

                 udfunc ( et, &amp;value )

              where:

                 et      an input double precision value 
                         representing the TDB ephemeris seconds time 
                         at which to determine the scalar value.

                 value   is the value of the geometric quantity 
                         at 'et'.

   udqdec     the name of the external routine that determines if
              the scalar quantity calculated by &quot;udfunc&quot; is decreasing.

              The calling sequence:

                 udqdec ( et, &amp;isdecr )

              where:

                 et       an input double precision value representing
                          the TDB ephemeris seconds time at at which
                          to determine the time derivative of 'udfunc'.

                 isdecr   a logical variable indicating whether
                          or not the scalar value returned by udfunc
                          is decreasing. 'isdecr' returns true if the 
                          time derivative of &quot;udfunc&quot; at 'et' is negative.

   relate     the scalar string comparison operator indicating 
              the numeric constraint of interest. Values are:
     
                 &quot;&gt;&quot;       value of scalar quantity greater than some
                           reference (refval).
     
                 &quot;=&quot;       value of scalar quantity equal to some
                           reference (refval).
     
                 &quot;&lt;&quot;       value of scalar quantity less than some
                           reference (refval).
     
                 &quot;ABSMAX&quot;  The scalar quantity is at an absolute
                           maximum.
     
                 &quot;ABSMIN&quot;  The scalar quantity is at an absolute
                            minimum.
     
                 &quot;LOCMAX&quot;  The scalar quantity is at a local 
                           maximum.
     
                 &quot;LOCMIN&quot;  The scalar quantity is at a local 
                           minimum.
     
              The caller may indicate that the region of interest
              is the set of time intervals where the quantity is
              within a specified distance of an absolute extremum.
              The argument 'adjust' (described below) is used to
              specified this distance.
     
              Local extrema are considered to exist only in the
              interiors of the intervals comprising the confinement
              window:  a local extremum cannot exist at a boundary
              point of the confinement window.
     
              relate is insensitive to case, leading and 
              trailing blanks.

   refval    is the reference value used to define an equality or
              inequality to  satisfied by the scalar quantity.
              The units of refval are those of the scalar quantity.

   adjust     the amount by which the quantity is allowed to vary
              from an absolute extremum.
                  
              If the search is for an absolute minimum is performed, 
              the resulting window contains time intervals when the 
              geometric quantity value has values between ABSMIN and 
              ABSMIN + adjust.
     
              If the search is for an absolute maximum, the
              corresponding range is  between ABSMAX - adjust and
              ABSMAX.
     
              'adjust' is not used for searches for local extrema,
              equality or inequality conditions and must have value
              zero for such searches.

   step       the double precision time step size to use in 
              the search.

              'step' must be short enough to for a search using this
              step size to locate the time intervals where the
              scalar quantity function is monotone increasing or
              decreasing. However, 'step' must not be *too* short,
              or the search will take an 

              The choice of 'step' affects the completeness but not
              the precision of solutions found by this routine; the
              precision is controlled by the convergence tolerance.
              See the discussion of the parameter SPICE_GF_CNVTOL for
              details.

              'step' has units of TDB seconds.

   nintvls    an integer value specifying the number of intervals in the 
              the internal workspace array used by this routine. 'nintvls'
              should be at least as large as the number of intervals
              within the search region on which the specified observer-target
              vector coordinate function is monotone increasing or decreasing. 
              It does no harm to pick a value of 'nintvls' larger than the
              minimum required to execute the specified search, but if chosen 
              too small, the search will fail.

   cnfine     a double precision SPICE window that confines the time
              period over which the specified search is conducted.
              cnfine may consist of a single interval or a collection
              of intervals. 

              In some cases the confinement window can be used to
              greatly reduce the time period that must be searched
              for the desired solution. See the Particulars section
              below for further discussion.
              
              See the Examples section below for a code example 
              that shows how to create a confinement window.
</PRE>
<h4><a name="Detailed_Output">Detailed_Output</a></h4>
<PRE>
 
   cnfine     is the input confinement window, updated if necessary
              so the control area of its data array indicates the
              window's size and cardinality. The window data are
              unchanged.

   result     is a SPICE window representing the set of time 
              intervals, within the confinement period, when the 
              specified geometric event occurs. 
 
              If `result' is non-empty on input, its contents 
              will be discarded before <b>gfuds_c</b> conducts its 
              search. 
 </PRE>
<h4><a name="Parameters">Parameters</a></h4>
<PRE>
 
   None.
 </PRE>
<h4><a name="Exceptions">Exceptions</a></h4>
<PRE>
 

   1)  In order for this routine to produce correct results, 
       the step size must be appropriate for the problem at hand. 
       Step sizes that are too large may cause this routine to miss 
       roots; step sizes that are too small may cause this routine 
       to run unacceptably slowly and in some cases, find spurious 
       roots. 
 
       This routine does not diagnose invalid step sizes, except 
       that if the step size is non-positive, an error is signaled 
       by a routine in the call tree of this routine. 
 
   2)  Due to numerical errors, in particular, 
 
          - Truncation error in time values 
          - Finite tolerance value 
          - Errors in computed geometric quantities 
 
       it is *normal* for the condition of interest to not always be 
       satisfied near the endpoints of the intervals comprising the 
       result window. 
 
       The result window may need to be contracted slightly by the 
       caller to achieve desired results. The SPICE window routine 
       <a href="wncond_c.html">wncond_c</a> can be used to contract the result window. 
 
   3)  If an error (typically cell overflow) occurs while performing  
       window arithmetic, the error will be diagnosed by a routine 
       in the call tree of this routine. 
 
   4)  If the relational operator `relate' is not recognized, an  
       error is signaled by a routine in the call tree of this 
       routine. 
       
   5)  If 'adjust' is negative, the error SPICE(VALUEOUTOFRANGE) will
       signal from a routine in the call tree of this routine. 

       A non-zero value for 'adjust' when 'relate' has any value other than 
       &quot;ABSMIN&quot; or &quot;ABSMAX&quot; causes the error SPICE(INVALIDVALUE) to
       signal from a routine in the call tree of this routine. 
  
   6)  If required ephemerides or other kernel data are not 
       available, an error is signaled by a routine in the call tree 
       of this routine. 
 
   7)  If the workspace interval count is less than 1, the error
       SPICE(VALUEOUTOFRANGE) will be signaled.

   8)  If the required amount of workspace memory cannot be
       allocated, the error SPICE(MALLOCFAILURE) will be
       signaled.

   9)  If any input string argument pointer is null, the error
       SPICE(NULLPOINTER) will be signaled.

   10) If any input string argument is empty, the error 
       SPICE(EMPTYSTRING) will be signaled.

   11) If either input cell has type other than SpiceDouble,
       the error SPICE(TYPEMISMATCH) is signaled.
</PRE>
<h4><a name="Files">Files</a></h4>
<PRE>
   Appropriate kernels must be loaded by the calling program before
   this routine is called.

   If the scalar function requires access to ephemeris data:

      - SPK data: ephemeris data for any body over the
        time period defined by the confinement window must be
        loaded. If aberration corrections are used, the states of
        target and observer relative to the solar system barycenter
        must be calculable from the available ephemeris data.
        Typically ephemeris data are made available by loading one
        or more SPK files via <a href="furnsh_c.html">furnsh_c</a>.

      - If non-inertial reference frames are used, then PCK
        files, frame kernels, C-kernels, and SCLK kernels may be
        needed.

   In all cases, kernel data are normally loaded once per program
   run, NOT every time this routine is called.
</PRE>
<h4><a name="Particulars">Particulars</a></h4>
<PRE>
   This routine provides a simpler, but less flexible interface
   than does the routine zzgfrel_ for conducting searches for events
   corresponding to an arbitrary user defined scalar quantity 
   function. Applications that require support for progress 
   reporting, interrupt handling, non-default step or refinement
   functions, or non-default convergence tolerance should call
   zzgfrel_ rather than this routine.

   This routine determines a set of one or more time intervals
   within the confinement window when the  scalar function
   satisfies a caller-specified constraint. The resulting set of
   intervals is returned as a SPICE window.

   udqdec Default Template
   =======================

   The user must supply a routine to determine whether sign of the
   time derivative of udfunc is positive or negative at 'et'. For
   cases where udfunc is numerically well behaved, the user
   may find it convenient to use a routine based on the below
   template. <a href="uddc_c.html">uddc_c</a> determines the truth of the expression

      d (udfunc)
      --         &lt; 0
      dt

   using the library routine <a href="uddf_c.html">uddf_c</a> to numerically calculate the
   derivative of udfunc using a three-point estimation. Use
   of gfdecr requires only changing the &quot;udfunc&quot; argument
   to that of the user provided scalar function passed to <b>gfuds_c</b>
   and defining the differential interval size, 'dt'. Please see 
   the Examples section for an example of gfdecr use.

   void gfdecr ( SpiceDouble et, SpiceBoolean * isdecr )
      {

      SpiceDouble         dt = h, double precision interval size;

      <a href="uddc_c.html">uddc_c</a>( udfunc, <a href="uddf_c.html">uddf_c</a>, et, dt, isdecr );

      return;
      }

   Below we discuss in greater detail aspects of this routine's
   solution process that are relevant to correct and efficient
   use of this routine in user applications.

   The Search Process
   ==================
   
   Regardless of the type of constraint selected by the caller, this
   routine starts the search for solutions by determining the time
   periods, within the confinement window, over which the specified
   scalar function is monotone increasing and monotone
   decreasing. Each of these time periods is represented by a SPICE
   window. Having found these windows, all of the quantity
   function's local extrema within the confinement window are known.
   Absolute extrema then can be found very easily. 
   
   Within any interval of these &quot;monotone&quot; windows, there will be at
   most one solution of any equality constraint. Since the boundary
   of the solution set for any inequality constraint is the set 
   of points where an equality constraint is met, the solutions of
   both equality and inequality constraints can be found easily
   once the monotone windows have been found.

   Step Size
   =========

   The monotone windows (described above) are found using a two-step
   search process. Each interval of the confinement window is
   searched as follows: first, the input step size is used to
   determine the time separation at which the sign of the rate of
   change of quantity function will be sampled. Starting at
   the left endpoint of an interval, samples will be taken at each
   step. If a change of sign is found, a root has been bracketed; at
   that point, the time at which the time derivative of the quantity 
   function is zero can be found by a refinement process, for 
   example, using a binary search.
   
   Note that the optimal choice of step size depends on the lengths
   of the intervals over which the quantity function is monotone:
   the step size should be shorter than the shortest of these
   intervals (within the confinement window).
   
   The optimal step size is *not* necessarily related to the lengths
   of the intervals comprising the result window. For example, if
   the shortest monotone interval has length 10 days, and if the
   shortest result window interval has length 5 minutes, a step size
   of 9.9 days is still adequate to find all of the intervals in the
   result window. In situations like this, the technique of using
   monotone windows yields a dramatic efficiency improvement over a
   state-based search that simply tests at each step whether the
   specified constraint is satisfied. The latter type of search can
   miss solution intervals if the step size is shorter than the
   shortest solution interval.

   Having some knowledge of the relative geometry of the targets and 
   observer can be a valuable aid in picking a reasonable step size. 
   In general, the user can compensate for lack of such knowledge by 
   picking a very short step size; the cost is increased computation 
   time. 

   Note that the step size is not related to the precision with which
   the endpoints of the intervals of the result window are computed.
   That precision level is controlled by the convergence tolerance.
   
   
   Convergence Tolerance
   =====================

   Once a root has been bracketed, a refinement process is used to 
   narrow down the time interval within which the root must lie. 
   This refinement process terminates when the location of the root 
   has been determined to within an error margin called the 
   &quot;convergence tolerance.&quot; The convergence tolerance used by this 
   routine is set via the parameter SPICE_GF_CNVTOL. 

   The value of SPICE_GF_CNVTOL is set to a &quot;tight&quot; value so that the 
   tolerance doesn't become the limiting factor in the accuracy of 
   solutions found by this routine. In general the accuracy of input 
   data will be the limiting factor. 
   
   Making the tolerance tighter than SPICE_GF_CNVTOL is unlikely to 
   be useful, since the results are unlikely to be more accurate. 
   Making the tolerance looser will speed up searches somewhat, 
   since a few convergence steps will be omitted. However, in most 
   cases, the step size is likely to have a much greater affect 
   on processing time than would the convergence tolerance.


   The Confinement Window 
   ====================== 
   
   The simplest use of the confinement window is to specify a time 
   interval within which a solution is sought. However, the 
   confinement window can, in some cases, be used to make searches 
   more efficient. Sometimes it's possible to do an efficient search 
   to reduce the size of the time period over which a relatively 
   slow search of interest must be performed. 
</PRE>
<h4><a name="Examples">Examples</a></h4>
<PRE>
   The numerical results shown for these examples may differ across
   platforms. The results depend on the SPICE kernels used as
   input, the compiler and supporting libraries, and the machine 
   specific arithmetic implementation. 

   Conduct a search on the range-rate of the vector from the Sun
   to the Moon. Define a function to calculate the value.

   Use the meta-kernel shown below to load the required SPICE
   kernels.

         KPL/MK

         File name: standard.tm

         This meta-kernel is intended to support operation of SPICE
         example programs. The kernels shown here should not be
         assumed to contain adequate or correct versions of data
         required by SPICE-based user applications.

         In order for an application to use this meta-kernel, the
         kernels referenced here must be present in the user's
         current working directory.


         \begindata

            KERNELS_TO_LOAD = ( 'de414.bsp',
                                'pck00008.tpc',
                                'naif0009.tls'  )

         \begintext

   Code:

   #include &lt;stdio.h&gt;
   #include &lt;stdlib.h&gt;
   #include &lt;string.h&gt;

   #include &quot;SpiceUsr.h&quot;
   #include &quot;SpiceZfc.h&quot;
   #include &quot;SpiceZad.h&quot;


   #define       MAXWIN    20000
   #define       TIMFMT    &quot;YYYY-MON-DD HR:MN:SC.###&quot;
   #define       TIMLEN    41
   #define       NLOOPS    7

   void    gfq     ( SpiceDouble et, SpiceDouble * value );
   void    gfdecrx ( void ( * udfunc ) ( SpiceDouble    et,
                                         SpiceDouble  * value ),
                     SpiceDouble    et, 
                     SpiceBoolean * isdecr );

   doublereal dvnorm_(doublereal *state);


   int main( int argc, char **argv )
      {

      /.
      Create the needed windows. Note, one interval
      consists of two values, so the total number
      of cell values to allocate is twice
      the number of intervals.
      ./
      SPICEDOUBLE_CELL ( result, 2*MAXWIN );
      SPICEDOUBLE_CELL ( cnfine, 2        );

      SpiceDouble       begtim;
      SpiceDouble       endtim;
      SpiceDouble       step;
      SpiceDouble       adjust;
      SpiceDouble       refval;
      SpiceDouble       beg;
      SpiceDouble       end;

      SpiceChar         begstr [ TIMLEN ];
      SpiceChar         endstr [ TIMLEN ];
      
      SpiceInt          count;
      SpiceInt          i;
      SpiceInt          j;

      ConstSpiceChar * relate [NLOOPS] = { &quot;=&quot;,
                                           &quot;&lt;&quot;,
                                           &quot;&gt;&quot;,
                                           &quot;LOCMIN&quot;,
                                           &quot;ABSMIN&quot;,
                                           &quot;LOCMAX&quot;,
                                           &quot;ABSMAX&quot;
                                         };

      printf( &quot;Compile date %s, %s\n\n&quot;, __DATE__, __TIME__ );

      /.  
      Load kernels.
      ./
      <a href="furnsh_c.html">furnsh_c</a>( &quot;standard.tm&quot; );
   
      /.  
      Store the time bounds of our search interval in the 'cnfine' 
      confinement window.
      ./
      <a href="str2et_c.html">str2et_c</a>( &quot;2007 JAN 01&quot;, &amp;begtim );
      <a href="str2et_c.html">str2et_c</a>( &quot;2007 APR 01&quot;, &amp;endtim );
   
      <a href="wninsd_c.html">wninsd_c</a> ( begtim, endtim, &amp;cnfine );

      /.  
      Search using a step size of 1 day (in units of seconds). The reference
      value is .3365 km/s. We're not using the adjustment feature, so
      we set 'adjust' to zero.
      ./
      step   = <a href="spd_c.html">spd_c</a>();
      adjust = 0.;
      refval = .3365;

      for ( j = 0;  j &lt; NLOOPS;  j++ )
         {

         printf ( &quot;Relation condition: %s \n&quot;,  relate[j] );

         /.
         Perform the search. The SPICE window 'result' contains 
         the set of times when the condition is met. 
         ./

         <b>gfuds_c</b> ( gfq, 
                   gfdecrx,
                   relate[j],
                   refval,
                   adjust,
                   step,
                   MAXWIN,
                   &amp;cnfine,
                   &amp;result );

         count = <a href="wncard_c.html">wncard_c</a>( &amp;result );

         /.
         Display the results.
         ./
         if (count == 0 ) 
            {
            printf ( &quot;Result window is empty.\n\n&quot; );
            }
         else
            {
            for ( i = 0;  i &lt; count;  i++ )
               {

               /.
               Fetch the endpoints of the Ith interval
               of the result window.
               ./
               <a href="wnfetd_c.html">wnfetd_c</a> ( &amp;result, i, &amp;beg, &amp;end );

               <a href="timout_c.html">timout_c</a> ( beg, TIMFMT, TIMLEN, begstr ); 
               <a href="timout_c.html">timout_c</a> ( end, TIMFMT, TIMLEN, endstr );

               printf ( &quot;Start time, drdt = %s \n&quot;, begstr );
               printf ( &quot;Stop time,  drdt = %s \n&quot;, endstr );

               }
               
            }

         printf(&quot;\n&quot;);
         
         }

      <a href="kclear_c.html">kclear_c</a>();
      return( 0 );
      }



   /.
   The user defined functions required by GFUDS.
      
      gfq    for udfunc
      gfdecr for udqdec
   ./



   /.
   -Procedure Procedure gfq
   ./

   void gfq ( SpiceDouble et, SpiceDouble * value )

   /.
   -Abstract

      User defined geometric quantity function. In this case,
      the range from the sun to the Moon at TDB time 'et'.
   
   ./
      {
      
      /. Initialization ./
      SpiceInt             targ   = 301;
      SpiceInt             obs    = 10;

      SpiceChar          * ref    = &quot;J2000&quot;;
      SpiceChar          * abcorr = &quot;NONE&quot;;

      SpiceDouble          state [6];
      SpiceDouble          lt;

      /.
      Retrieve the vector from the Sun to the Moon in the J2000 
      frame, without aberration correction.
      ./
      <a href="spkez_c.html">spkez_c</a> ( targ, et, ref, abcorr, obs, state, &amp;lt );

      /.
      Calculate the scalar range rate corresponding the
     'state' vector.   
      ./

      *value = dvnorm_( state );

      return;
      }



   /.
   -Procedure gfdecrx
   ./
   
   void gfdecrx ( void ( * udfunc ) ( SpiceDouble    et,
                                      SpiceDouble  * value ),
                  SpiceDouble    et, 
                  SpiceBoolean * isdecr )

   /.
   -Abstract

      User defined function to detect if the function derivative
      is negative (the function is decreasing) at TDB time 'et'.
   ./
      {
         
      SpiceDouble         dt = 10.;
     
      /.
      Determine if &quot;udfunc&quot; is decreasing at 'et'.

      <a href="uddc_c.html">uddc_c</a> - the GF function to determine if
                 the derivative of the user defined
                 function is negative at 'et'.

      <a href="uddf_c.html">uddf_c</a>   - the SPICE function to numerically calculate the 
                 derivative of 'udfunc' at 'et' for the 
                 interval [et-dt, et+dt].
      ./

      <a href="uddc_c.html">uddc_c</a>( udfunc, et, dt, isdecr );

      return;
      }


   The program outputs:

      Relation condition: = 
      Start time, drdt = 2007-JAN-02 00:35:19.574 
      Stop time,  drdt = 2007-JAN-02 00:35:19.574 
      Start time, drdt = 2007-JAN-19 22:04:54.899 
      Stop time,  drdt = 2007-JAN-19 22:04:54.899 
      Start time, drdt = 2007-FEB-01 23:30:13.428 
      Stop time,  drdt = 2007-FEB-01 23:30:13.428 
      Start time, drdt = 2007-FEB-17 11:10:46.540 
      Stop time,  drdt = 2007-FEB-17 11:10:46.540 
      Start time, drdt = 2007-MAR-04 15:50:19.929 
      Stop time,  drdt = 2007-MAR-04 15:50:19.929 
      Start time, drdt = 2007-MAR-18 09:59:05.959 
      Stop time,  drdt = 2007-MAR-18 09:59:05.959 
      
      Relation condition: &lt; 
      Start time, drdt = 2007-JAN-02 00:35:19.574 
      Stop time,  drdt = 2007-JAN-19 22:04:54.899 
      Start time, drdt = 2007-FEB-01 23:30:13.428 
      Stop time,  drdt = 2007-FEB-17 11:10:46.540 
      Start time, drdt = 2007-MAR-04 15:50:19.929 
      Stop time,  drdt = 2007-MAR-18 09:59:05.959 
      
      Relation condition: &gt; 
      Start time, drdt = 2007-JAN-01 00:00:00.000 
      Stop time,  drdt = 2007-JAN-02 00:35:19.574 
      Start time, drdt = 2007-JAN-19 22:04:54.899 
      Stop time,  drdt = 2007-FEB-01 23:30:13.428 
      Start time, drdt = 2007-FEB-17 11:10:46.540 
      Stop time,  drdt = 2007-MAR-04 15:50:19.929 
      Start time, drdt = 2007-MAR-18 09:59:05.959 
      Stop time,  drdt = 2007-APR-01 00:00:00.000 
      
      Relation condition: LOCMIN 
      Start time, drdt = 2007-JAN-11 07:03:58.988 
      Stop time,  drdt = 2007-JAN-11 07:03:58.988 
      Start time, drdt = 2007-FEB-10 06:26:15.439 
      Stop time,  drdt = 2007-FEB-10 06:26:15.439 
      Start time, drdt = 2007-MAR-12 03:28:36.404 
      Stop time,  drdt = 2007-MAR-12 03:28:36.404 
      
      Relation condition: ABSMIN 
      Start time, drdt = 2007-JAN-11 07:03:58.988 
      Stop time,  drdt = 2007-JAN-11 07:03:58.988 
      
      Relation condition: LOCMAX 
      Start time, drdt = 2007-JAN-26 02:27:33.766 
      Stop time,  drdt = 2007-JAN-26 02:27:33.766 
      Start time, drdt = 2007-FEB-24 09:35:07.816 
      Stop time,  drdt = 2007-FEB-24 09:35:07.816 
      Start time, drdt = 2007-MAR-25 17:26:56.150 
      Stop time,  drdt = 2007-MAR-25 17:26:56.150 
      
      Relation condition: ABSMAX 
      Start time, drdt = 2007-MAR-25 17:26:56.150 
      Stop time,  drdt = 2007-MAR-25 17:26:56.150 
</PRE>
<h4><a name="Restrictions">Restrictions</a></h4>
<PRE>
   1) Any kernel files required by this routine must be loaded
      before this routine is called.
</PRE>
<h4><a name="Literature_References">Literature_References</a></h4>
<PRE>
   None.
</PRE>
<h4><a name="Author_and_Institution">Author_and_Institution</a></h4>
<PRE>
   N.J. Bachman   (JPL)
   E.D. Wright    (JPL)
 </PRE>
<h4><a name="Version">Version</a></h4>
<PRE>
   -CSPICE Version 1.0.0, 22-FEB-2010 (EDW) 
</PRE>
<h4><a name="Index_Entries">Index_Entries</a></h4>
<PRE>
   GF user defined scalar function search
</PRE>
<h4>Link to routine gfuds_c source file <a href='../../../src/cspice/gfuds_c.c'>gfuds_c.c</a> </h4>

      </td>
    </tr>
  </tbody>
</table>

   <pre>Wed Jun  9 13:05:24 2010</pre>

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